Growth and Maintenance of a Tornado Vortex by Upscale Inertial Production of Turbulence

The growth of a tornado vortex by the inward merger of vorticity produced away from the tornado via baroclinic production is well known.  Once the vortex defining the growing tornado reaches critical levels of inertial stability defined by its inertial frequency, the tornado becomes increasing efficient in suppressing turbulence interacting with its circulation, much as the static stability suppresses turbulence according to the Brunt-Vasallai frequency during the stable negative buoyancy production of turbulence.  Unlike buoyancy production, however, the energy drawn from the turbulence will be entrained directly into the tornadic vortex, through vortex mergers, creating an increasingly laminar and energetic vortex.  This process can be formulated in a manner equivalent to the buoyancy production model used in turbulence closure.  The formulation and the impact on tornado development will be described at the oral presentation.

The growth of a tornado vortex by the inward merger of vorticity produced away from the tornado via baroclinic production is well known.  Once the vortex defining the growing tornado reaches critical levels of inertial stability defined by its inertial frequency, the tornado becomes increasing efficient in suppressing turbulence interacting with its circulation, much as the static stability suppresses turbulence according to the Brunt-Vasallai frequency during the stable negative buoyancy production of turbulence.  Unlike buoyancy production, however, the energy drawn from the turbulence will be entrained directly into the tornadic vortex, through vortex mergers, creating an increasingly laminar and energetic vortex.  This process can be formulated in a manner equivalent to the buoyancy production model used in turbulence closure.  The formulation and the impact on tornado development will be described at the oral presentation.